Survival outcomes and prognostic indicators for gastric cancer patients with positive peritoneal wash cytology but no peritoneal metastasis after radical gastrectomy

Clinical impact of gastrectomy for gastric cancer patients with positive lavage cytology without gross peritoneal dissemination

BACKGROUND

The prognosis of gastric cancer patients with positive lavage cytology without gross peritoneal dissemination (P0CY1) is poor. The survival benefit of gastrectomy for these patients has not been established.

PATIENTS AND METHODS

In this population-based cohort study, we investigated the impact of radical gastrectomy with lymph node dissection for P0CY1 patients. Patients who were diagnosed with Stage IV gastric cancer from 2008 to 2015 in all nine cancer-designated hospitals in a tertiary medical area were listed. Patients who were diagnosed with histologically proven adenocarcinoma in both the primary lesion and lavage cytology during the operation or a diagnostic laparoscopic examination were enrolled. Patients with a gross peritoneal lesion or other metastatic lesions were excluded. The primary outcome was the adjusted hazard ratio (aHR) of gastrectomy for overall survival. We also evaluated the survival time in patients who underwent gastrectomy or chemotherapy in comparison to patients managed without primary surgery or with best supportive care.

RESULTS

One hundred patients were enrolled. The aHR (95% confidence interval) of gastrectomy was 0.677 (0.411-1.114, p = 0.125). The median survival time in patients who received gastrectomy (n = 74) was 21.7, while that in patients managed without primary surgery (n = 30) was 20.5 months (p = 0.155). The median survival time in patients who received chemotherapy (n = 76) was 23.0 months, while that in patients managed without chemotherapy was 8.6 months (p < 0.001).

CONCLUSION

Gastrectomy was not effective for improving the survival time in patients with P0CY1 gastric cancer. Surgeons should prioritize the performance of chemotherapy over surgery as the initial treatment.

Current treatment strategies for patients with only peritoneal cytology positive stage IV gastric cancer

Gastric cancer (GC) is one of the most common malignancies worldwide and surgery remains the only potentially curative treatment option for it. Although a significant proportion of GC patients are found with distant metastases already at the initial diagnosis. Peritoneal dissemination is the most common site of metastases. Positive peritoneal cytology (Cy1) is associated with poor long-term outcomes; thus, these patients are considered as stage IV even if macroscopic carcinomatosis is absent. Currently, there is no clear evidence for the most optimal treatment for this distinct subpopulation of the stage IV cohort. Available strategies vary from palliative chemotherapy to upfront gastrectomy. This comprehensive review summarized current evidence of different treatment strategies for Cy1 GC including roles of surgery, systemic and intraperitoneal chemotherapy.